Recent genetic work suggests that the genus Stenella is paraphyletic, and it is likely that the Delphininae will be restructured in coming years (LeDuc et al. 1999). This species might move to a different genus.

Justification:
The species is widespread, but abundance has not been estimated for the mid- and east Atlantic (and where abundance estimates do exist for other regions, these are low) and there are bycatches and directed takes in West Africa of unknown, but likely escalating, scale.

The Clymene Dolphin is found only in the tropical and subtropical Atlantic Ocean, including the Caribbean Sea and Gulf of Mexico (Jefferson et al. 1995). This species has a notable warm-water preference, although there are records as far north as New Jersey on the U.S. east coast and as far south as southern Brazil (Zerbini and Kotas 1998). The limits on the West African coast are not well known, but extend from at least the equator north to Mauritania. The Clymene Dolphin is not known to enter the Mediterranean Sea (Perrin and Mead 1994, Jefferson and Curry 2003, Fertl et al. 2003).

The map shows where the species may occur based on oceanography. The species has not been recorded for all the states within the hypothetical range as shown on the map. States for which confirmed records of the species exist are included in the list of native range states. States within the hypothetical range but for which no confirmed records exist are included in the Presence Uncertain list.

Abundance has only been estimated for the northern Gulf of Mexico and US east coast (6,575 (CV=36%) and 6,086 (CV=93%), respectively — Waring et al. 2008). However, considering the difficulty of distinguishing it from similarly marked species at sea, it may not be as rare as it would seem to be (Perrin and Mead 1994). Based on capture records, S. clymene appears to be the most common cetacean in Ghana's coastal waters (Van Waerebeek et al. 2000).

This is a deep-water, oceanic species, not often seen near shore (unless deep water approaches the coast).

Very few stomachs have been examined, and there are even fewer observations of feeding behaviour reported in the literature. Clymene Dolphins apparently feed predominantly on small fish (including myctophids) and squid at moderate depths (Jefferson and Curry 2003).

Although they are known to be taken by harpoon occasionally in dolphin fisheries in the Caribbean (especially St. Vincent in the Lesser Antilles), and incidental captures in fishing nets do occur throughout much of the range, the Clymene Dolphin is not known to suffer any heavy exploitation at present (Jefferson and Curry 2003). The only possible exception may be off the coast of West Africa, where this species is possibly one of several taken in large numbers in tuna purse seines in the Gulf of Guinea (Van Waerebeek et al. 2000).

Clymene Dolphins are captured incidentally in gillnets in Venezuelan waters and utilized for longline shark bait and for human consumption (Perrin and Mead 1994).